Volcano the size of Arizona discovered

Sep. 6, 2013
|

Tamu Massif, a monster volcano roughly the size of Arizona, ranks among the largest such structures in our solar system, 'Nature' reports by way of a Nature Geoscience study. But Tamu Massif differs from typical seamounts in that it has a nearly indiscernible slope—around 1 degree near the summit (which sits 6,500 feet below the surface), and much less near the base, National Geographic reports. And lead author William Sager says other oceanic plateaus could also be volcanoes: "There may be bigger ones out there." / Newslook

by Arden Dier, Newser

by Arden Dier, Newser

Scientists have made a surprising discovery in the Pacific Ocean about 1,000 miles east of Japan: Earth's largest volcano.

Tamu Massif is a monster at 280 miles by 400 miles, or roughly the size of Arizona, and ranks among the largest such structures in our solar system, Nature reports by way of a Nature Geoscience study.

The existence of Tamu Massif has been long known, but geologists believed it to be composed of several volcanoes that merged.

Research conducted in 2010 and 2012 changed things. That's when researchers sailed over Tamu Massif and sent seismic waves through it using air guns.

"We saw what appear to be lava flows going out from the center of the volcano in all directions, with no obvious large secondary source of volcanism," says lead author William Sager - meaning this is "one huge volcano." (Though one that has been inactive for as many as 145 million years.)

But Tamu Massif differs from typical seamounts in that it has a nearly indiscernible slope-around 1 degree near the summit (which sits 6,500 feet below the surface), and much less near the base, National Geographic reports. And Sager says other oceanic plateaus could also be volcanoes: "There may be bigger ones out there."

Newser is a USA TODAY content partner providing general news, commentary and coverage from around the Web. Its content is produced independently of USA TODAY.